<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>动画初体验</title>
    <style>
        .box{
            width: 100px;
            height: 100px;
            background-color: #00f;
            animation: move 5s;
        }
        @keyframes move {
            0%{
                background-color: #00f;
            }
            100%{
                background-color: #0f0;
                border-radius: 50px;
            }
        }
    </style>
</head>
<body>
<div class="box"></div>
<div></div>
<div></div>
<div></div>
<div></div>
</body>
</html>